Unit 1 Flashcards
(28 cards)
Explain what is meant by the phrase “the contructive brain”
The brain constructs the reality we perceive around us. Our brain gathers information so that we can have percepions and guesses (higher-order cognition) about the world around us; that is, it’s constructing the experiences we have
List the three layers of the meninges from the skull to the surface of the cortex
From the skull to the surface of the cortex, the three layers of the meninges are the dura mater, arachnoid mater, and pia mater.
What is the role of the autonomic nervous system (ANS)? Compare and contrast its two subdivisions
The autonomic system controls our visceral organs. The two subdivisions are the parasympathetic and the symptathetic system. The parasympathetic system is known as the rest and digest, which allows us to calm down. While contrast to this is the sympathetic system, also known as fight or flight response. This constricts bloods vessels and increases heart rate
Match the following terms to their definitions.
Gyrus
Sulcus
Cortical sheet
[a ‘ridge’, a ‘valley’, outer surface of cortex composed of gray matter]
the gyrus is a ‘ridge’ of the cerebral cortex
the sulcus is a ‘valley’ of the cerebral cortex
the cortical sheet is the outer surface covering of the cerebral cortex, composed of gray matter
Give an example of how layers of the gray matter are different in different regions of cortex.
Regions across cerebral cortex differ in the thickness of each of their 6 layers of cells depending on the function of the region. For example, in the primary visual cortex, input layer IV is much larger than that of the primary motor cortex, which has a larger output layer V (indicative of how V1 allocates more resources for signal acquisition/input than M1).
Name two characteristics that were used to define Brodmann’s areas of the brain.
Brodmann areas of the cerebral cortex are defined by its cytoarchitecture (histological structure and cellular organization)
Math each strucutr eof a neuron to its functions. Dendrite, cell body, axon, axon terminal [‘summation’, ‘communication’, ‘output’, ‘input’]
dendrite = input
cell body = summation
axon = output
axon terminal = communication
What is one thing the study of split-brain patients tells us about how the two hemispheres of the brain work?
The study of split-brain patients demonstrates that the state of consciousness is not reliant on interhemispheric communication via the corpus callosum.
The study of split-brain patients demonstrates that each hemisphere has access only to the subset of brain functions within that specific hemisphere.
Why is myelin important to neuronal communication?
Myelin is important, because it substantially increases the speed at which ions flow down an axon due to saltatory conduction, which in turn increases neuronal firing rates. Myelin allows ions to “take a shortcut” and flow to the next node of Ranvier, where it continues its membrane potential changes down the axon, and the cycle repeats with every myelin sheath.
What does the Bell-Magendie law about the spinal cord describe?
The Bell-Magendie law is the finding that the anterior spinal nerve roots contain only motor fibers and posterior roots only sensory fibers and that nerve impulses are conducted in only one direction in each case.
Match the term for each type of lateralty with the approprate definition.
Unilateral, Bilateral, Ipsilateral, Contralateral.
Unilateral = on one side of the body
Bilateral = on both sides of the body
Ipsilateral = two things on the same side of the body
Contralateral = two things on opposite sides of the body
Outline a comparison of the 3 major types of blood vessels. Be sure to include comparisons of vessel structure and function.
Artery: Pressurized blood via heart contractions cause blood to leave heart and travel to cells throughout body; lined by thick muscular vessel walls to handle the high systolic pressures.
Vein: Thinner vessel wall than arteries; pipeline for blood to return to the heart (with exceptions like pulmonary vein); blood returns to heart via muscle contractions and gravity, but significantly less pressurized
Capillary: Location for gas/nutrient exchange and entry point for drugs and infectious agents; lined by single-cell endothelium.
What is the circle of Willis?
The circle of Willis is a circle of arteries that supply blood to the brain. This arrangement of blood vessels allows for collateral blood flow to the brain
Describe how the blood-brain barrier is formed (i.e., what are its components, not its development). What are the functions of the blood-brain barrier?
The blood brain barrier has layers of glial cells such as astrocytes, that limit what is able to cross through. The functions of the BBB are to inhibit threats to the brain such as toxins and viruses. Only fat soluable-molecules are able to pass through.
Match the following terms to their associated descriptions.
Basement membrane, endothelial cells/endothelium, intercellular cleft, gap junction, tight junction. [Cells that line the interior surface of blood vessels and lymphatic vessels, forming an interface between circulating blood or lymph in the lumen (open tube within the blood vessel) and the rest of the vessel wall, A specialized intercellular connection between many types of animal cells. They directly connect the cytoplasm of two cells, which allows various molecules, ions, and electrical impulses to directly pass through a regulated gate between cells, A channel between two cells through which molecules may travel and gap junctions and tight junctions may be present,A thin, fibrous, extracellular matrix that separates the lining of an internal or external body surface from underlying connective tissue, Areas where the membranes of two adjacent cells join together to form a barrier. They bind cells together, prevent molecules from passing in between the cells, and also help maintain the polarity of cells.]
Basement membrane = D
Endothelial cells = A
Intercellular cleft = C
Gap Junction = B
Tight Junctions= E
What are bridging veins? Why do we worry about bridging veins in cases of head trauma?
Bridging veins are veins that drain the neural tissue and puncture (‘bridge’) through the dura mater to drain into the venous sinuses. They may tear with trauma and bleed to cause a subdural hematoma. Bridging veins have a higher risk of rupturing from trauma from a fall in patients who suffer from alcoholism. Long-term alcoholism both weakens the vein vessel walls throughout the body and shrinks the brain, which puts greater stress on the bridging veins specifically.
Why is a lumbar puncture useful? Include how the flow of cerebral spinal fluid (CSF) is important to its use.
A lumbar puncture is usefull because it allows us to get a look at what is going on inside the brain. We can find biomarkers that are then used to figure out what may be going wrong.
Match the following terms related to the cerebral spinal fluid system to their definitions.
Ventricles, CSF, Choroid plexus, Arachnoid granulations [The specialized cells lining the ventricles responsible for the creation of CSF/CSF-filled cavities in the brain, four total (left, right, third, and fourth)/The bubble-like portions of the arachnoid mater (middle layer of meninges) into the draining venous sinus system that are responsible for the removal of CSF from around the brain; CSF is ‘recycled’ into the blood stream/The fluid surrounding the brain and spinal cord that cushions the nervous system; fluid is similar to blood plasma]
Ventricales = B
CSF=D
Choroid plexus = A
Arachnoid granulations = C
Cranial nerves
a set of 12 specialized nerves that act as the PNS (motor control
and sensory info) to the head and neck
Meninges
the three protective layers of tissue between the brain and the skull
Dura mater
the durable, leathery outer protective layer of the meninges
Arachnoid mater
the spider web-like middle protective layer of the meninges
that is filled with cerebral spinal fluid
Pia mater
the thin, shiny, inner protective layer of the meninges that “shrinkwraps” the brain
Brodmann’s areas
- Histologically defined areas of the brain, grouped by similar
cell types. Used to refer to locations in the brain.
